1,2-dichloroethane, commonly known as ethylene dichloride ("EDC") is a compound manufactured industrially on a scale of several million tons per year, which, on pyrolysis is converted into vinyl chloride monomer and hydrochloric acid. Vinyl chloride monomer is polymerized into poly(vinyl) chloride ("PVC"), a widely used polymer.
Catalysts and processes for the production of chlorinated hydrocarbons by oxychlorination have been well established for a number of years. Specifically, oxychlorination of ethylene with oxygen and hydrochloric acid in the presence of a catalyst to produce 1,2-dichloroethane is widely practiced in commercial installations throughout the world.
The catalyst composition, that is, the catalyst itself and its support material, can be in the form of a fluidized bed of particles which are fluidized during the reaction, or in the form of a fixed bed of particles. In the oxychlorination of ethylene with such a catalytic fixed bed, the catalysts advantageously contain copper II chloride on a carrier in combination with promoters, such as potassium chloride.
In oxychlorination processes, major concerns include productivity, efficient catalyst utilization, HCl conversion, and capital costs.
EP 0146925 filed Dec. 19, 1984 discloses a method for the oxychlorination of ethylene utilizing oxygen-enriched air. In two-reactor installations, the total quantity of ethylene and hydrogen chloride is fed to the first reactor while the oxygen is divided between the two reactors. This reference teaches utilization of three or more reactors when dividing both hydrogen chloride and oxygen between the first two serially connected reactors.
There is a need in the art for an improved method of oxychlorinating ethylene.